Era 2 Preparation

Level up your Laboratory. Level 14 is needed to get Era 2 Coupling by the end of Era 2 without a plus account. Level 11 is needed with a plus account. You can't upgrade your Laboratory too much.
Be sure to save enough money (805,000) to upgrade your Engine shed right after we hit Era 2.
Get Coupling. If you won't have Coupling by Era 2 but you can get it less than a day into Era 2, you should finish the research for it. 1 to 2 days is more questionable but I wouldn't blame you for getting Coupling. More than 2 days, IMO forget about Coupling and save your research points for Era 2.
Have at least 2-3 free tracks to begin Era 2. Or connect to all Era 2 RGs by using a Map Of Goods. You can't haul a new RG if you aren't connected to it.